The following are examples of recent translational studies which we have either initiated or played a major collaborative role and which have been completed and are at the stage of preparation of a manuscript : - We studied nestin expression in benign and malignant nerve sheath tumors from patients with neurofibromatosis 1 and found its correlation with a malignant phenotype. We also found increased expression of nestin in histologically atypical areas of otherwise benign tumors that correlate with increased PET uptake, suggesting that it may serve as a marker of tumor progression. - We evaluated expression of the ganglioside GD2 in large number of solid pediatric tumors and found high expression in osteosarcoma and Ewing sarcoma. Our data will help design a clinical trial targeting GD2 in these tumors. - We evaluated NY-ESO expression pediatric synovial sarcomas and other solid tumors in this age group, which will lead to a new clinical trial at the NCI. - We found that c-kit negative gastrointestinal stromal tumors (GIST) with mutation in the succinate dehydrogenase (SDH)B gene, which lack expression of SDHB, show high expression of EGFR, but lack EGFR gene amplification or mutation. These data suggest that c-kit negative (pediatric) GIST may be yet another tumor example of translational upregulation of EGFR by tumor hypoxia.- We collaborate on a study that seeks to identify molecular therapeutic targets in pediatric pontine gliomas, by performing immunohistochemical staining and evaluation of a panel of proteins